Cincinnati, colloquially nicknamed Cincy, is the most populous city in Hamilton County, Ohio, United States, and its county seat. Settled in 1788, the city is located on the northern side of the confluence of the Licking and Ohio rivers, the latter of which marks the state line with Kentucky. The third-most populous city in Ohio with a population of 309,317 at the 2020 census, Cincinnati serves as the economic and cultural hub of the tri-state Cincinnati metropolitan area, Ohio's most populous metropolitan area and the nation's 30th-largest at over 2.3 million residents.